<!DOCTYPE html>
<html>

<head>
    <!-- 背景测试 -->
    <meta charset="utf-8">
    <title>背景测试</title>



    <style>
        .bg {
            background: #00ff00 url('https://www.runoob.com/try/demo_source/smiley.gif') no-repeat 20% 20%/50%;
        }
    </style>

</head>

<body>
    <div class="bg">
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
        <p>This is some text</p>
    </div>

</body>

</html>